<?php
/**
 * sh404SEF - SEO extension for Joomla!
 *
 * @author      Yannick Gaultier
 * @copyright   (c) Yannick Gaultier 2012
 * @package     sh404sef
 * @license     http://www.gnu.org/copyleft/gpl.html GNU/GPL
 * @version     4.1.0.1559
 * @date		2013-04-25
 */

defined('JPATH_PLATFORM') or die;

/**
 * Pagination Class.  Provides a common interface for content pagination for the
 * Joomla! Platform.
 *
 * @package     Joomla.Platform
 * @subpackage	HTML
 * @since       11.1
 */
class JPagination extends JObject
{
  /**
	 * @var    integer  The record number to start displaying from.
	 * @since  11.1
   */
  public $limitstart = null;

  /**
	 * @var    integer  Number of rows to display per page.
	 * @since  11.1
   */
  public $limit = null;

  /**
	 * @var    integer  Total number of rows.
	 * @since  11.1
   */
  public $total = null;

  /**
	 * @var    integer  Prefix used for request variables.
	 * @since  11.1
   */
  public $prefix = null;

  /**
	 * @var    boolean  View all flag
	 * @since  11.1
   */
  protected $_viewall = false;

  /**
   * Additional URL parameters to be added to the pagination URLs generated by the class.  These
   * may be useful for filters and extra values when dealing with lists and GET requests.
   *
   * @var		array
	 * @since  11.1
   */
  protected $_additionalUrlParams = array();

  /**
   * Constructor.
   *
	 * @param   integer  $total       The total number of items.
	 * @param   integer  $limitstart  The offset of the item to start at.
	 * @param   integer  $limit       The number of items to display per page.
	 * @param   string   $prefix      The prefix used for request variables.
	 *
	 * @since   11.1
   */
	public function __construct($total, $limitstart, $limit, $prefix = '')
  {
    // Value/type checking.
    $this->total		= (int) $total;
    $this->limitstart	= (int) max($limitstart, 0);
    $this->limit		= (int) max($limit, 0);
    $this->prefix		= $prefix;

		if ($this->limit > $this->total)
		{
      $this->limitstart = 0;
    }

    if (!$this->limit)
    {
      $this->limit = $total;
      $this->limitstart = 0;
    }

    /*
     * If limitstart is greater than total (i.e. we are asked to display records that don't exist)
     * then set limitstart to display the last natural page of results
     */
		if ($this->limitstart > $this->total - $this->limit)
		{
      $this->limitstart = max(0, (int)(ceil($this->total / $this->limit) - 1) * $this->limit);
    }

    // Set the total pages and current page values.
    if ($this->limit > 0)
    {
      $this->set('pages.total', ceil($this->total / $this->limit));
      $this->set('pages.current', ceil(($this->limitstart + 1) / $this->limit));
    }

    // Set the pagination iteration loop values.
    $displayedPages	= 10;
    $this->set('pages.start', $this->get('pages.current') - ($displayedPages / 2));
		if ($this->get('pages.start') < 1)
		{
      $this->set('pages.start', 1);
    }
		if (($this->get('pages.start') + $displayedPages) > $this->get('pages.total'))
		{
      $this->set('pages.stop', $this->get('pages.total'));
			if ($this->get('pages.total') < $displayedPages)
			{
        $this->set('pages.start', 1);
			}
			else
			{
        $this->set('pages.start', $this->get('pages.total') - $displayedPages + 1);
      }
		}
		else
		{
      $this->set('pages.stop', ($this->get('pages.start') + $displayedPages - 1));
    }

    // If we are viewing all records set the view all flag to true.
		if ($limit == 0)
		{
      $this->_viewall = true;
    }
  }

  /**
   * Method to set an additional URL parameter to be added to all pagination class generated
   * links.
   *
   * @param	string	$key	The name of the URL parameter for which to set a value.
   * @param	mixed	$value	The value to set for the URL parameter.
   *
   * @return	mixed	The old value for the parameter.
   *
	 * @since   11.1
   */
  public function setAdditionalUrlParam($key, $value)
  {
    // Get the old value to return and set the new one for the URL parameter.
    $result = isset($this->_additionalUrlParams[$key]) ? $this->_additionalUrlParams[$key] : null;

    // If the passed parameter value is null unset the parameter, otherwise set it to the given value.
		if ($value === null)
		{
      unset($this->_additionalUrlParams[$key]);
    }
		else
		{
      $this->_additionalUrlParams[$key] = $value;
    }

    return $result;
  }

  /**
	 * Method to get an additional URL parameter (if it exists) to be added to
	 * all pagination class generated links.
   *
   * @param	string	$key	The name of the URL parameter for which to get the value.
   *
   * @return	mixed	The value if it exists or null if it does not.
   *
	 * @since   11.1
   */
  public function getAdditionalUrlParam($key)
  {
    $result = isset($this->_additionalUrlParams[$key]) ? $this->_additionalUrlParams[$key] : null;

    return $result;
  }

  /**
   * Return the rationalised offset for a row with a given index.
   *
	 * @param   integer  $index  The row index
	 *
	 * @return  integer  Rationalised offset for a row with a given index.
	 *
	 * @since   11.1
   */
  public function getRowOffset($index)
  {
    return $index +1 + $this->limitstart;
  }

  /**
   * Return the pagination data object, only creating it if it doesn't already exist.
   *
   * @return	object	Pagination data object.
	 *
	 * @since   11.1
   */
  public function getData()
  {
    static $data;
		if (!is_object($data))
		{
      $data = $this->_buildDataObject();
    }
    return $data;
  }

  /**
   * Create and return the pagination pages counter string, ie. Page 2 of 4.
   *
   * @return	string	Pagination pages counter string.
	 *
	 * @since   11.1
   */
  public function getPagesCounter()
  {
    // Initialise variables.
    $html = null;
		if ($this->get('pages.total') > 1)
		{
      $html .= JText::sprintf('JLIB_HTML_PAGE_CURRENT_OF_TOTAL', $this->get('pages.current'), $this->get('pages.total'));
    }
    return $html;
  }

  /**
	 * Create and return the pagination result set counter string, e.g. Results 1-10 of 42
   *
   * @return	string	Pagination result set counter string.
	 *
	 * @since   11.1
   */
  public function getResultsCounter()
  {
    // Initialise variables.
    $html = null;
    $fromResult = $this->limitstart + 1;

    // If the limit is reached before the end of the list.
		if ($this->limitstart + $this->limit < $this->total)
		{
      $toResult = $this->limitstart + $this->limit;
    }
		else
		{
      $toResult = $this->total;
    }

    // If there are results found.
		if ($this->total > 0)
		{
      $msg = JText::sprintf('JLIB_HTML_RESULTS_OF', $fromResult, $toResult, $this->total);
      $html .= "\n".$msg;
    }
		else
		{
      $html .= "\n".JText::_('JLIB_HTML_NO_RECORDS_FOUND');
    }

    return $html;
  }

  /**
   * Create and return the pagination page list string, ie. Previous, Next, 1 2 3 ... x.
   *
   * @return	string	Pagination page list string.
	 *
	 * @since   11.1
   */
  public function getPagesLinks()
  {
    $app = JFactory::getApplication();

    // Build the page navigation list.
    $data = $this->_buildDataObject();

    $list = array();
    $list['prefix']			= $this->prefix;

    $itemOverride = false;
    $listOverride = false;

		$chromePath = JPATH_THEMES . '/' . $app->getTemplate() . '/html/pagination.php';
    if (file_exists($chromePath))
    {
			include_once $chromePath;
			if (function_exists('pagination_item_active') && function_exists('pagination_item_inactive'))
			{
        $itemOverride = true;
      }
			if (function_exists('pagination_list_render'))
			{
        $listOverride = true;
      }
    }

    // Build the select list
		if ($data->all->base !== null)
		{
      $list['all']['active'] = true;
      $list['all']['data'] = ($itemOverride) ? pagination_item_active($data->all) : $this->_item_active($data->all);
		}
		else
		{
      $list['all']['active'] = false;
      $list['all']['data'] = ($itemOverride) ? pagination_item_inactive($data->all) : $this->_item_inactive($data->all);
    }

		if ($data->start->base !== null)
		{
      $list['start']['active'] = true;
      // is this prev?
      $options = array();
      if($data->previous->base !== null && $data->previous->base == $data->start->base) {
        $options['rel'] = 'prev';
      }
      $list['start']['data'] = ($itemOverride) ? pagination_item_active($data->start, $options) : $this->_item_active($data->start, $options);
    } else {
      $list['start']['active'] = false;
      $list['start']['data'] = ($itemOverride) ? pagination_item_inactive($data->start) : $this->_item_inactive($data->start);
    }
		if ($data->previous->base !== null)
		{
      $list['previous']['active'] = true;
      $list['previous']['data'] = ($itemOverride) ? pagination_item_active($data->previous, array( 'rel' => 'prev')) : $this->_item_active($data->previous, array( 'rel' => 'prev'));
    }
		else
		{
      $list['previous']['active'] = false;
      $list['previous']['data'] = ($itemOverride) ? pagination_item_inactive($data->previous) : $this->_item_inactive($data->previous);
    }

    $list['pages'] = array(); //make sure it exists
    foreach ($data->pages as $i => $page)
    {
			if ($page->base !== null)
			{
        $list['pages'][$i]['active'] = true;
        // is this next or prev?
        $options = array();
        if($data->next->base !== null && $data->next->base == $page->base) {
          $options['rel'] = 'next';
        } else if($data->previous->base !== null && $data->previous->base == $page->base) {
          $options['rel'] = 'prev';
        }
        $list['pages'][$i]['data'] = ($itemOverride) ? pagination_item_active($page, $options) : $this->_item_active($page, $options);
      } else {
        $list['pages'][$i]['active'] = false;
        $list['pages'][$i]['data'] = ($itemOverride) ? pagination_item_inactive($page) : $this->_item_inactive($page);
      }
    }

		if ($data->next->base !== null)
		{
      $list['next']['active'] = true;
      $list['next']['data'] = ($itemOverride) ? pagination_item_active($data->next, array( 'rel' => 'next')) : $this->_item_active($data->next, array( 'rel' => 'next'));
    }
    else
		{
      $list['next']['active'] = false;
      $list['next']['data'] = ($itemOverride) ? pagination_item_inactive($data->next) : $this->_item_inactive($data->next);
    }

		if ($data->end->base !== null)
		{
      $list['end']['active'] = true;
      // is this next?
      $options = array();
      if($data->next->base !== null && $data->next->base == $data->end->base) {
        $options['rel'] = 'next';
      }
      $list['end']['data'] = ($itemOverride) ? pagination_item_active($data->end, $options) : $this->_item_active($data->end, $options);
    }

    else {
      $list['end']['active'] = false;
      $list['end']['data'] = ($itemOverride) ? pagination_item_inactive($data->end) : $this->_item_inactive($data->end);
    }

		if ($this->total > $this->limit)
		{
      return ($listOverride) ? pagination_list_render($list) : $this->_list_render($list);
    }
		else
		{
      return '';
    }
  }

  /**
   * Return the pagination footer.
   *
   * @return	string	Pagination footer.
	 *
	 * @since   11.1
   */
  public function getListFooter()
  {
    $app = JFactory::getApplication();

    $list = array();
    $list['prefix']			= $this->prefix;
    $list['limit']			= $this->limit;
    $list['limitstart']		= $this->limitstart;
    $list['total']			= $this->total;
    $list['limitfield']		= $this->getLimitBox();
    $list['pagescounter']	= $this->getPagesCounter();
    $list['pageslinks']		= $this->getPagesLinks();

		$chromePath = JPATH_THEMES . '/' . $app->getTemplate() . '/html/pagination.php';
    if (file_exists($chromePath))
    {
			include_once $chromePath;
			if (function_exists('pagination_list_footer'))
			{
        return pagination_list_footer($list);
      }
    }
    return $this->_list_footer($list);
  }

  /**
   * Creates a dropdown box for selecting how many records to show per page.
   *
	 * @return  string  The HTML for the limit # input box.
	 *
	 * @since   11.1
   */
  public function getLimitBox()
  {
    $app = JFactory::getApplication();

    // Initialise variables.
    $limits = array ();

    // Make the option list.
		for ($i = 5; $i <= 30; $i += 5)
		{
      $limits[] = JHtml::_('select.option', "$i");
    }
    $limits[] = JHtml::_('select.option', '50', JText::_('J50'));
    $limits[] = JHtml::_('select.option', '100', JText::_('J100'));
    $limits[] = JHtml::_('select.option', '0', JText::_('JALL'));

    $selected = $this->_viewall ? 0 : $this->limit;

    // Build the select list.
		if ($app->isAdmin())
		{
			$html = JHtml::_(
				'select.genericlist',
				$limits,
				$this->prefix . 'limit',
				'class="inputbox" size="1" onchange="Joomla.submitform();"',
				'value',
				'text',
				$selected
			);
    }
		else
		{
			$html = JHtml::_(
				'select.genericlist',
				$limits,
				$this->prefix . 'limit',
				'class="inputbox" size="1" onchange="this.form.submit()"',
				'value',
				'text',
				$selected
			);
    }
    return $html;
  }

  /**
   * Return the icon to move an item UP.
   *
	 * @param   integer  $i          The row index.
   * @param	boolean			$condition	True to show the icon.
   * @param	string			$task		The task to fire.
   * @param	string			$alt		The image alternative text string.
   * @param	boolean			$enabled	An optional setting for access control on the action.
   * @param	string			$checkbox	An optional prefix for checkboxes.
   *
   * @return	string	Either the icon to move an item up or a space.
	 *
	 * @since   11.1
   */
  public function orderUpIcon($i, $condition = true, $task = 'orderup', $alt = 'JLIB_HTML_MOVE_UP', $enabled = true, $checkbox='cb')
  {
		if (($i > 0 || ($i + $this->limitstart > 0)) && $condition)
		{
      return JHtml::_('jgrid.orderUp', $i, $task, '', $alt, $enabled, $checkbox);
    }
		else
		{
      return '&#160;';
    }
  }

  /**
   * Return the icon to move an item DOWN.
   *
	 * @param   integer  $i          The row index.
	 * @param   integer  $n          The number of items in the list.
   * @param	boolean			$condition	True to show the icon.
   * @param	string			$task		The task to fire.
   * @param	string			$alt		The image alternative text string.
   * @param	boolean			$enabled	An optional setting for access control on the action.
   * @param	string			$checkbox	An optional prefix for checkboxes.
   *
   * @return	string	Either the icon to move an item down or a space.
	 *
	 * @since   11.1
   */
  public function orderDownIcon($i, $n, $condition = true, $task = 'orderdown', $alt = 'JLIB_HTML_MOVE_DOWN', $enabled = true, $checkbox='cb')
  {
		if (($i < $n - 1 || $i + $this->limitstart < $this->total - 1) && $condition)
		{
      return JHtml::_('jgrid.orderDown', $i, $task, '', $alt, $enabled, $checkbox);
    }
		else
		{
      return '&#160;';
    }
  }

	/**
	 * Create the HTML for a list footer
	 *
	 * @param   array  $list  Pagination list data structure.
	 *
	 * @return  string  HTML for a list footer
	 *
	 * @since   11.1
	 */
  protected function _list_footer($list)
  {
    $html = "<div class=\"list-footer\">\n";

    $html .= "\n<div class=\"limit\">".JText::_('JGLOBAL_DISPLAY_NUM').$list['limitfield']."</div>";
    $html .= $list['pageslinks'];
    $html .= "\n<div class=\"counter\">".$list['pagescounter']."</div>";

    $html .= "\n<input type=\"hidden\" name=\"" . $list['prefix'] . "limitstart\" value=\"".$list['limitstart']."\" />";
    $html .= "\n</div>";

    return $html;
  }

	/**
	 * Create the html for a list footer
	 *
	 * @param   array  $list  Pagination list data structure.
	 *
	 * @return  string  HTML for a list start, previous, next,end
	 *
	 * @since   11.1
	 */
  protected function _list_render($list)
  {
    // Reverse output rendering for right-to-left display.
    $html = '<ul>';
    $html .= '<li class="pagination-start">'.$list['start']['data'].'</li>';
    $html .= '<li class="pagination-prev">'.$list['previous']['data'].'</li>';
		foreach ($list['pages'] as $page)
		{
      $html .= '<li>'.$page['data'].'</li>';
    }
    $html .= '<li class="pagination-next">'. $list['next']['data'].'</li>';
    $html .= '<li class="pagination-end">'. $list['end']['data'].'</li>';
    $html .= '</ul>';

    return $html;
  }

	/**
	 * Method to create an active pagination link to the item
	 *
	 * @param   JPaginationObject  &$item  The object with which to make an active link.
	 *
	 * @return   string  HTML link
	 *
	 * @since    11.1
	 */
	protected function _item_active(&$item)
  {
    $app = JFactory::getApplication();
    if ($app->isAdmin())
    {
			if ($item->base > 0)
			{
				return "<a title=\"" . $item->text . "\" onclick=\"document.adminForm." . $this->prefix . "limitstart.value=" . $item->base
					. "; Joomla.submitform();return false;\">" . $item->text . "</a>";
      }
			else
			{
				return "<a title=\"" . $item->text . "\" onclick=\"document.adminForm." . $this->prefix
					. "limitstart.value=0; Joomla.submitform();return false;\">" . $item->text . "</a>";
      }
    }
    else {
      return "<a title=\"".$item->text."\" href=\"".$item->link. '"' .(empty($options['rel']) ? '' : ' rel="' . $options['rel'] . '"'). " class=\"pagenav\">".$item->text."</a>";
    }
  }

	/**
	 * Method to create an inactive pagination string
	 *
	 * @param   object  &$item  The item to be processed
	 *
	 * @return  string
	 *
	 * @since   11.1
	 */
  protected function _item_inactive(&$item)
  {
    $app = JFactory::getApplication();
		if ($app->isAdmin())
		{
      return "<span>".$item->text."</span>";
    }
		else
		{
      return "<span class=\"pagenav\">".$item->text."</span>";
    }
  }

  /**
   * Create and return the pagination data object.
   *
   * @return	object	Pagination data object.
	 *
	 * @since   11.1
   */
  protected function _buildDataObject()
  {
    // Initialise variables.
    $data = new stdClass;
    $sefConfig = & Sh404sefFactory::getConfig();

    // build a "limit" string
    $limitString = '&limit=' . $this->limit;

    // Build the additional URL parameters string.
    $params = '';
    if (!empty($this->_additionalUrlParams))
    {
      foreach($this->_additionalUrlParams as $key => $value)
      {
        $params .= '&'.$key.'='.$value;
      }
    }

    $data->all = new JPaginationObject(JText::_('JLIB_HTML_VIEW_ALL'), $this->prefix);
		if (!$this->_viewall)
		{
      $data->all->base	= '0';
      $data->all->link	= JRoute::_($params.'&'.$this->prefix.'limitstart=');
    }

    // Set the start and previous data objects.
    $data->start	= new JPaginationObject(JText::_('JLIB_HTML_START'), $this->prefix);
    $data->previous	= new JPaginationObject(JText::_('JPREV'), $this->prefix);

    if ($this->get('pages.current') > 1)
    {
      $page = ($this->get('pages.current') -2) * $this->limit;

			// Set the empty for removal from route
			//$page = $page == 0 ? '' : $page;

      $data->start->base	= '0';
      $data->start->link	= JRoute::_($params.'&'.$this->prefix.'limitstart=0');
      $data->previous->base	= $page;
      $data->previous->link	= JRoute::_($params.'&'.$this->prefix.'limitstart='.$page.$limitString);
      
      if($sefConfig->insertPaginationTags) {
        $pageInfo = & Sh404sefFactory::getPageInfo();
        $pageInfo->paginationPrevLink = $data->previous->link;
      }
    }

    // Set the next and end data objects.
    $data->next	= new JPaginationObject(JText::_('JNEXT'), $this->prefix);
    $data->end	= new JPaginationObject(JText::_('JLIB_HTML_END'), $this->prefix);

    if ($this->get('pages.current') < $this->get('pages.total'))
    {
      $next = $this->get('pages.current') * $this->limit;
      $end  = ($this->get('pages.total') -1) * $this->limit;

      $data->next->base	= $next;
      $data->next->link	= JRoute::_($params.'&'.$this->prefix.'limitstart='.$next.$limitString);
      $data->end->base	= $end;
      $data->end->link	= JRoute::_($params.'&'.$this->prefix.'limitstart='.$end.$limitString);
      
      if($sefConfig->insertPaginationTags) {
        $pageInfo = & Sh404sefFactory::getPageInfo();
        $pageInfo->paginationNextLink = $data->next->link;
      }
      
    }

    $data->pages = array();
    $stop = $this->get('pages.stop');
    for ($i = $this->get('pages.start'); $i <= $stop; $i ++)
    {
      $offset = ($i -1) * $this->limit;
			// Set the empty for removal from route
			//$offset = $offset == 0 ? '' : $offset;

      $data->pages[$i] = new JPaginationObject($i, $this->prefix);
      if ($i != $this->get('pages.current') || $this->_viewall)
      {
        $data->pages[$i]->base	= $offset;
        $data->pages[$i]->link	= JRoute::_($params.'&'.$this->prefix.'limitstart='.$offset.$limitString);
      }
    }
    return $data;
  }
}

/**
 * Pagination object representing a particular item in the pagination lists.
 *
 * @package		Joomla.Framework
 * @subpackage	HTML
 * @since		1.5
 */
class JPaginationObject extends JObject
{
  public $text;
  public $base;
  public $link;
  public $prefix;

  public function __construct($text, $prefix = '', $base = null, $link = null)
  {
    $this->text = $text;
    $this->prefix = $prefix;
    $this->base = $base;
    $this->link = $link;
  }
}
